Measuring Temperature with Arduino - 5 Sensors

Today I’ll show you five different temperature sensors that you can easily use with an Arduino.

We have measured temperature in previous Arduino projects, usually using the trusty DHT11 temperature and humidity sensor. For non-critical applications, it certainly works and has the added advantage of also reading humidity.

But there are many other temperature sensors you can use with an Arduino, all of them fairly inexpensive. Many of these sensors offer improved performance over the DHT22 (and its cousin the DHT11).

Today we'll start with the DHT22 and use an Adafruit library to get it working quickly. Then we’ll move on to some other temperature sensors:

The AM2320, a similar device to the DHT22 that uses the I2C bus to communicate.

The TMP36 and LM35 precision temperature sensors. These devices output a calibrated linear analog voltage to represent temperature.

And a real high-precision sensor, the MCP9808 module from Adafruit.

Here is what you can expect to see today:

00:00 - Introduction
02:18 - DHT22
08:37 - AM2320
13:27- TMP36 & LM35
21:09 - MCP9808

There is an article on the website with the schematics and the code I used, although most of the examples are included with the Adafruit libraries.

You’ll also find a vibrant community to chat about these sensors and pretty well anything robotic or electronic on the DroneBot Workshop Forums. Why don’t you join us? While you're there you can make suggestions for any other video or articles you’d like to see.

I hope you enjoy the video!

[boonedockjourneyman]

Your detail in the YouTube description is excellent. You’re the only creator in this field who puts in this effort. Thank you.

[henrygraterol]

I wasn't expecting to gain so much knowledge from this video based on the title, but the amount of detail and the way it is organized is excellent. Thank you fpr sharing your knowledge. Great job!

[aetpagwtom]

nice video, im using the 22 these days, but 25 years ago had a project using the LM35, i had to design n calibrate a current to voltage circuit, run that into a microcontroller, with code witten in assembly, then send the values out as 8 bit serial data, with a pseudo RS232 transmission, (no uart), .. just clocked... easy peasy today, .., thx again for the videos., cheers.

[johnjordan]

I'll chime in for the Dallas DS18B20 1-wire sensor as well. I made small PCBs that chain together with cheap phone cable to monitor the plumbed areas of an out building. The Arduinos turn on heaters via TTL controlled power strips.

[PhG]

Great video and very well explained. Maybe a futher addition with the legendary 18DS20 sensor. I've been working with this for years and it's very reliable.

[tinkmarshino]

whoa.. hot stuff today!!! at 10:36 you said to attach the two pull up resistor to ground and showed them to positive.. Since you called them pull up's I imagine the schematic was correct you just said ground when you meant power.. outstanding.. I am going to make a temp humidity sensor for indoor and out soor temp sensing.. this was a good one to get ideas from.. thanks Bill..

[tubeDude]

As always, excellent video!!! Those that give a thumbs-down, probably can't spell Electronics!
I was surprised you didn't include the popular *DS18B20*

[rondlh]

Another nice option is the DS18B20, an accurate digital sensor that only needs power and 1 signal line, you can run many sensors in parallel, power can even be omitted when you use parasitic power. Definitely worth a look. Also the way 3D printers measure temperatures with a thermistor could be examined. No mention of multi-sampling to reduce noise and increase accuracy?

[jamesgoacher]

Restored my sanity with a well presented and details article, thank you.

[rlsimpso]

Thanks you for another great tutorials. This is especially timely because I was discussing using temperate sensors with Arduino as part of a home automation project just a few hours before receiving the notification. This saved me a lot of time. Thanks again.

[JerryEricsson]

One other thing, I picked up one of those M5STICK-C devices. It is a PICO ESP32 device with built in OLED Color Screen, on board lipo battery and several built in sensors. It also has a GROVE connector and breaks out 8 pins on top for hat's that run sensor packages. I purchased an environmental sensor that has an on board DHT12 BMP280 and BMM150. It reads out temp, humidity and ordinal direction. Neat little device, and I have been playing with it recently to try and figure out all the things I can do with it. I got both the HAT and the GROVE with the same sensors. The problem I have with it is this, when run the temp never stabilizes and continues to go up no matter where I sit it down, or if I hold it in my hand. Humidity does stabilize and in my shop, inside a metal building with all sorts of things from my ham radios to the big screen TV and several computer crunching numbers all around, the direction is usually way off. Why can't I depend on this thing for a relatively accurate temp? It does give me the F scale which was a real selling point for the tiny fully wireless/blue tooth device with a duel core processor at 240 MHZ.

[alaincesarini]

Excellent video and clear tutorial as usual. I suggest an extension of this video by studying DS18b20 and NTC 10K or 100K sensors.

[mikbbb]

@10:31 You say connecte to GND but on the annimation you connect it to 5V

[MadLabZ]

Thank you for the upload, your videos are always to the point and professional. YOU DA MAN!!!!

[anvz]

The atmega328 has an optional internal reference of 1.1V for analog conversion. It should be better if you are reading temperatures below 110 C

[NewAgeDIY]

I have a project in mind that will record the temperature on 3 areas of my gaming computer. The output will be displayed on a small OLED display mounted on the glass panel of the computer. The fact that this setup will be independent from the computer itself will give the gamer access to the system temperature without having to count on software running on the computer screen.

[JohnClulow]

Great review of ambient temperature sensors. For specific localized temperature measurement in projects like my coffee roaster, I have used the MAX6675 module (K-thermocouple) and that seems to work very well.

[Ivor_Nastyboil]

I'm quite a fan of the GYBMEP module, as it also includes barometric pressure and is nice and small (I2C as well).

[borsi]

Again what a super video. Thank you very much for all these interesting informations! I hope you go on with your projects. Boris 🇨🇭

[henrikjensen]

With the analog sensors the ATmega328 has an internal 1.1V reference that could be used, that would improve the sensitivity even more and limit maximum temperature a bit.
Another way to increase sensitivity and open for lower temperatures is to use a LM34 (Fahrenheit) sensor, you can, of course, scale to Celsius if you wish.
To get better support for negative temperature on LM35 (and LM34) requires a diode, a resistor and one extra ADC input.